1. Technical Field
The present invention relates to a bilayered bone graft device, and more particularly, to a bilayered bone graft device with a composite structure.
2. Background
A variety of ceramic-based bone graft substitutes, such as calcium phosphate and calcium sulfate, have been developed and can provide support, fill voids, and enhance biological repair of skeletal defects. However, their inherent brittleness and fatigue failure limits their application to low-load-bearing or non-load-bearing bones in the human body. Although conventional high-temperature solid-state sintering could be used to fabricate compact high strength ceramic materials, it is not suitable for the preparation of materials containing polymers, drugs, and other bioactive molecules.
Recently, a high strength calcium phosphate ceramic has been developed at room temperature using a cement compaction procedure for bone substitute. However, it must be emphasized that the successful design of a bone substitute material requires an appreciation of the structure of the bone. Bone is a composite structure consisting of apatite nanocrystals incorporated within a collagen matrix, and extensive research has been carried out in the bio-inspired composite composed of a polymer and a ceramic that aptly resembles the morphology and properties of the natural bone.